High-pressure hot water cleaner

ABSTRACT

Cleaning apparatus having a tank of hot medium from which heat is transferred to a cleaning fluid conducted through a coiled heat transfer tube. Cold cleaning fluid is delivered by a continuously operative liquid pump to the heat transfer tube from which the heated and pressurized cleaning fluid is delivered to a spray gun having a trigger for initiating an automatic multistage cycle to sequentially spray a surface with water, detergent and a mixture thereof at elevated temperatures.

g a l 4 l Minted metres Patent [151 mnemm lt/tlaelltntlo 1 Felt, 29,11.972

[54] llllllGlHl-WRE5SKUIRE HUT WATER 2,128,263 8/1938 Ofeldt ..137/336 X@LIEAWER 2,165,321 7/1939 Wertz "222/146 HA 2,884,197 4/1959 Wh'ttell,Jr. ..237 8 BP [72] lnventor: Joseph G. Maehado, R0. Box 371 l, lModesto 95 352 Primary Examiner-Robert B. Reeves 22 i June 23, 9 9Assistant ExaminerJ0hn P. Shannon [21] A l N 835 M Attorney-Owen,Wiclcersham 8L Erickson [57] AlEiS'llllilAtC'l [52] US. Cl, ..222/23,222/146 ll-l, 1765/104 Cleaning apparatus having a tank of hot mediumfrom which [51] h heat is transferred to a cleaning fluid conductedthrough a [58] fi gj g"546335) 5 1 9 coiled heat transfer tube. Coldcleaning fluid is delivered by a 131 continuously operative liquid pumpto the heat transfer tube from which the heated and pressurized cleaningfluid is delivered to a spray gun having a trigger for initiating anauto- [56] References Cited matic multistage cycle to sequentially spraya surface with UNITED STATES PATENTS water, detergent and a mixturethereof at elevated temperatures. 2,000,467 5/1935 Lindseth ..l65/l04 X2,582,134 1/1952 Kimmell et a1 ..l65/l04 X 16 Cilaims, 13 DrawingFigures PATENTEDFEBEQ I972 13, SARA-2O SHEET 2 OF 5 PATENTEUFEBZQ 19723,6W5A2O SHEET 3 OF 5 ELEASAZO PATENTEDFEB29 |972 SHEET UF 5HIGH-PRESSURE HGT WATIER (CLEANER This invention relates to apparatusfor applying sprays of cleaning fluid under elevated pressures andtemperatures.

An important object of the present invention is to providepower-operated apparatus through which heated cleaning fluid may bedelivered in spray form at predetermined temperature and pressures undersafe and trouble-free conditions and in selectively controlled amounts.

In accordance with the present invention the cleaning fluid is heated toits elevated delivery temperature by being con ducted through a coiledheat transfer tube submerged within a body of heating fluid storedwithin an insulated tank. The cleaning fluid is delivered to the tankunder pressure by a liquid pump which is continuously operative tosupply the cleaning fluid only at a lower temperature. Less frequentbreakdown and maintenance is therefore required for the pump.Solenoid-controlled valves are also associated with the apparatus forselectively introducing a cleaning fluid such as a detergent solutioninto the water continuously delivered by the pump to the heat transfertube. A solenoid operated bypass control valve is also provided so thatthe cold liquid may be directly delivered to the outlet end of the heattransfer tube. A flexible conduit connects the outlet to a spray gunwhich has a trigger-operated switch through which the operator mayselectively and sequentially control the supply of cold liquid, hotliquid, and detergent to the spray gun.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of con struction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIG. I is a top plan view of one form of apparatus constructed inaccordance with the present invention.

FIG. 2 is a side sectional view through the apparatus takensubstantially through a plane indicated by section line 2-2 in FIG. I.

FIG. 3 is a front elevational view of the apparatus shown in FIGS. I and2.

FIG. 3 is a schematic diagram of the heating device associated with theapparatus of FIGS. 1-3.

FIG. 5 is a partial top plan view of another form of cleaning apparatusconstructed in accordance with the present invention.

FIG. 6 is a side sectional view taken substantially through a planeindicated by section line t5h in FIG. 5.

FIG. 7 is a partial side sectional view showing a third form of theinvention.

FIG. fl is a top plan view of a fourth form of the invention.

FIG. 9 is a partial front elevational view of the apparatus shown inFIG. b.

FIG. III is a side sectional view taken substantially through a planeindicated by section line IIII0 in FIG. 8.

FIG. II is a schematic view of the heating device associated with theapparatus of FIGS. til-ill.

FIG. I2 is a side elevational view with parts shown in section of thespray gun and control box associated with the apparatus of the presentinvention.

FIG. I3 is an electrical circuit diagram associated with the controlsshown in FIG. I2.

Referring now to the drawings in detail, and initially to FIGS. I, 2 and3, the cleaning apparatus generally denoted by reference numeral Id maybe rendered portable by mounting on a wheeled vehicle frame 12. In oneembodiment of the in vention, a generally rectangular frame 12 issupported by a pair of rear wheel assemblies I4 and a pair of forwardcaster wheel assemblies lid. A pulling rod I8 may be pivotally connected to the forward end of the vehicle frame. The forward end may alsomount a vertical rack 2d on which flexible hose 22 may be stored, thehose 22 being connected to a spray gun device 24 as shown in FIG. I2 andto a control box 26 having a plurality of operational stageindicatorsltl, 3b, 32, and 34.

With continued reference to FIGS. I and 2 in particular, it will benoted that a vertical insulated tank lid is fixedly mounted on thevehicle frame adjacent the forward end. The upper opened end of the tankmay be closed by a conical exhaust dome 3?). An outlet fitting II! ismounted by the tanlt ad jacent its upper end and projects therefromforwardly. The flexible, fluid delivery hose 22 is connected to thefitting lb.

The outlet fitting Ml projects into the tank above a body ofheat-storing fluid, such as water d2 and is connected by a T- coupling44 to the outlet end of an externally finned and coiled heat transfertube in. The end of the heat transfer tube 46 opposite the outlet end towhich the coupling is con nected, is connected to an inlet fittingfixedly mounted by the tank 36. It will be apparent therefore, thatcleaning fluid conducted through the heat transfer tube d6 will beelevated in temperature by transfer of heat from the heat-storing water42. The temperature of the body of water $2 is maintained at apredetermined value by means of a thermostatic sensing element d3fixedly mounted by the tank and projecting into the water.

The temperature of the heat storing water is heated by means of aheating assembly which includes a pair of gas bur ners 50 that extendhorizontally through an enclosing jacket 52 at the bottom of the tank 35as more clearly seen in FIG. 2. A plurality of vertical flue gasconduits fi l communicate with the interior of the jacket 52 and conductflue gas upwardly therefrom through the interior of the tank in heattransfer relation to the body of water d2, in order to maintain the sameat its elevated temperature. By controlling the supply of fuel to theburners 52, the temperature of the flue gases and the water I?! may beregulated. Accordingly, as shown in FIG. il, the fuel or gas for theburners is supplied through an inlet valve 5d and a pair of parallelflow valves 58 and 649 to the burners. The flow valves 58 and 6dregulate the quantity of fuel supplied to the burners. Further, thequantity of fuel conducted through the valve as may be varied undercontrol of the thermostatic sensing element t! aforementioned.Accordingly, when the temperature of the heat-storing water 4 2 withinthe tank reaches a predetermined upper limit, this temperature is sensedby the element Ali so as to close the flow valve db thereby reducing thequantity of fuel supplied to the burner. If the temperature of the waterI2 drops below a lower limit, as sensed by the element dd, the valve M9is opened so as to increase the quantity of fuel supplied to the burnersand the amount of heat generated thereby.

The cleaning fluid is supplied to the inlet fitting 4% on the tank at arelatively low inlet temperature by means of a delivery conduit is inturn connected by a solenoid-operated bypass valve assembly 64 to a pumpdischarge conduit 6h. The conduit es is connected to the discharge endof a liquid pump dd, the inlet end being connected by a fitting 7b to asuitable source of water. The pump 658 may be continuously maintained inoperation by means of a motor 72 which is fixedly mounted on the vehicleframe I2 adjacent its rear end below the pump A supporting platform 7 5fixedly mounts the pump 68 in spaced relation above the motor 52 whichis drivingly connected to the pump by means of an endless drivebelt 76.Thus, in one operative condition of the solenoid operated valve assemblyMl, cold water under pressure is delivered by the pump 46% throughconduits dd and s2 to the inlet end of the heat transfer tube ltiathrough inlet fitting 418. In the other operative position of thesolenoid-operated valve assembly b4, the cold water is delivered fromconduit as and valve assembly 64 to a bypass conduit 78 which isdirectly connected to the outlet fitting id through the coupling idthereby bypassing the heat transfer tube. 46 by means of which thecleaning fluid is elevated in temperature.

A solenoid-controlled device till! is also provided as shown in FIGS. Iand 2 having an intake conduit b2 drawing a cleaning fluid such asdetergent tldfrom a container b6 fixedly mounted on the vehicle framebetween the motor 72 and the tanl; 3th. Wen operating, thesolenoid-controlled device bill will introduce the detergent into theconduit :66 through fitting dd.

Thus, cold water, hot water and a mixture of cold or hot water anddetergent may be selectively delivered to the spray gun 24 by theflexible hose 22.

FIGS. 5 and 6 illustrate one modification of the apparatus previouslydescribed, generally referred to by reference numeral It). The apparatusit) includes a stationary frame 12 which mounts all of the componentshereinbefore described in connection with FIGS. 1 through 4 except forthe heating facility for the heat-storing water 42 within the insulatedtank 36. Instead of a gas burner type of heating facility, a coiledheating conduit 90 is mounted within the tank inside of the coiledconfiguration of the heat transfer tube 46' through which the cleaningfluid is conducted from the conduit 62 to the outlet fitting ill). Theheating conduit 90) is connected by a central conduit portion 92 to aninlet fitting 94 while the upper end of the heating conduit is connectedto an outlet fitting 96. A heating fluid which is heated externally ofthe apparatus may thereby be circulated through the heating conduit 90in order to regulate and maintain the elevated temperature of theheat-storing water 42 under control of the thermostatic sensing element48.

The body of heat-storing water 42 may alternatively be heated externallyof the apparatus and circulated through the tank 36, in which case, thelevel of the water within the tank will be controlled by a float valve98 as shown in FIG. 7 illustrating a third form of the invention. Whenheating the water externally of the apparatus through any suitableheating means, the apparatus may be lightened by taking advantage of asuitable heating facility that may be available.

Referring now to FIGS. 8, 9 and 10, another form of apparatus generallyreferred to by reference numeral 100 is shown. The apparatus we includesa frame assembly I02 which supports a horizontally positioned,cylindrical tank I04 vertically spaced above a supporting floor M96. Aheat-insulating jacket I08 surrounds the tank between axial end plates Iand H2. Chamber forming closures 114 and H6 are hingedly connected tothe axial ends of the tank and may be opened for component repair andreplacement purposes. The closure 114. at one axial end of the tankinternally mounts a burner assembly 118 within an air inlet chamber 120which is partitioned by wall 1122 from an exhaust chamber 124 to whichan exhaust conduit 126 is connected. Also, mounted on the closure IE4 isa blower device 128 having a discharge conduit 1130 in communicationwith the chamber 120. The other closure I16 encloses at the oppositeaxial end of the tank, a flow return space 132.

A plurality of elongated, heat transfer tubes 134 extend between and aresupported by the end plates Ill) and 112 for conducting flue gas fromthe inlet chamber I20 to the return chamber 132. The flue gas which isthe product of combustion of the fuel supplied to the burner assemblyI18, will be at a very high temmrature. Accordingly, as this flue gasflows through the heat transfer tubes 134, it heats the heat-storingfluid 2136 which is sealed within the tank between the end plates 1110and 132. The flue gas reaching the return chamber 132 then travels in areturn direction through another set of heat transfer tubes I38 to theexhaust chamber 3124. Thus, the flue gas undergoes bidirectional flowthrough the tank between the inlet chamber 126 and the exhaust chamber124 under the inducement of the blower 128. The heat stored within thefluid 136 is transferred to the cleaning fluid conducted through anexternally finned, coiled heat transfer tube 1 M) encircling some of theheat transfer tubes E34 and 138 as shown in FIG. 10 in order to elevatethe temperature of cleaning fluid.

Mounted below the horizontally disposed tank 104, on the frame assembly192, is a liquid pump 68' similar in operation and construction to thepump 68 hereinbefore described in connection with FIGS. 1-4. The pump isdriven through a direct drive coupling M2 by an electric motor 72 inorder to continuously supply cold water under pressure to the dischargeconduit 66. Detergent may be introduced into the water through thefitting 88' connected to the solenoidoperated device fit). The detergent84 is drawn from the container 86' through conduit 82. Water or amixture of water and detergent is supplied to the inlet end of thecoiled heat transfer tube Ml through the bypass control valve assembly64' which is also connected by the bypass conduit 78' directly to theoutlet end of the coiled heat transfer tube Mt). The outlet end of theheat transfer tube Mil: is connected by an outlet fitting 410 as shownin FIGS. 8 and 9 to the flexible hose 22 for delivery of cleaning fluidto the spray gun.

The source of heat for the apparatus is obtained from the burnerassembly 1114 to which a regulated and controlled quantity of fuel issupplied as shown in FIG. II in a manner similar to that hereinbeforedescribed in connection with FIG. 4. Accordingly, the fuel is admittedthrough an inlet valve 56' and conducted through a pair of parallelflow-regulating valves 53 and 6t? to the burner assembly 114. Athermostatic sensing element 48' controls the opening and closing of theflow control valve 61) in order to change the quantity of fuel fed tothe burner assembly and the amount of heat generated thereby.

Referring now to FIG. )12 it will be observed that the spray gun device24 is of a conventional type having a trigger element 144 which inaddition to opening a valve to permit discharge of cleaning fluid, as inthe case of a conventional spray gun, also actuates an electrical switchM6 as shown in the electrical circuit diagram of FIG. 13, toautomatically produce a sequential change in operation as indicated byextinction of one of the indicator lamps 28, 3t), 32 and 34 andillumination of another of the indicator lamps. Thus, the cleaning fluidfrom the outlet fitting of the heating tank is connected by the flexiblehose 22 to a special flexible conduit M8 by means of a fitting I50conducting the cleaning fluid in surrounding relation to an electricalcable 152 through which the trigger-operated switch associated with thespray gun is connected to the control box 26 on which the indicatorlamps are mounted.

As shown in FIG. 13, a DC source of electrical voltage is connected tothe control box on which the indicator lamps are mounted by the positivevoltage line I54 and the negative voltage line 156. Each indicator lampis electrically connected to one of the four electronic shift registersE53 mounted within the control box. Upon momentary closing of thetrigger-operated switch 146, a first relay is energized so as to openthe normally closed relay switch 162 disconnecting the positive-voltageline I54 from an input signal line I64. At the same time, normallyopened relay switch 1166 is closed so as to supply a positive voltage tothe shift line 163. In this fashion, each time the switch 146 is closed,a shift signal is established in order to cause a shift from oneoperational stage to another, in view of the electrical interconnectionbetween the shift registers 158 corresponding to each operational stage.When an operational shift occurs, the indicator lamp of a precedingshift register is extinguished and the lamp associated with thefollowing shift register illuminated.

Each of the shift registers I58 are commercially available components,the terminals of which are wired into the circuit as shown in FIG. 13 inorder to control operation of the apparatus. The first stage shiftregister transfers the stage-changing signals to the other shiftregisters which in turn control energization of the relays I70, 1'72 and174 as each signal pulse is generated by momentary closing of switchI46. Energization of the relay I'7lll closes the normally opened relayswitch 176 so as to complete a circuit through the hot rinse controlsolenoid 173 between the voltage lines 54 and 156. Solenoid 178 isassociated with the bypass valve assembly 64 as described in connectionwith FIGS. 1 through 4 for example. Thus, when the solenoid 178 isenergized, cold water delivered by the pump 68 is routed through conduit62 to the heat transfer tube 46. When the solenoid B78 is deenergized,cold water is supplied directly through bypass conduit '78 to the outletfitting 40.

Energization of the relay E72 closes the normally opened relay switches180 and $82 to simultaneously energize the hot rinse solenoid i178 andthe detergent solenoid llll l associated with the detergent supplydevice as. Thus, when the relay N2 is energized, heated detergent willbe supplied to the spray gun device. linergization of the relay lid onthe other hand, closes the normally open relay switch to complete anenergizing circuit only through the detergent solenoid llld l fordelivery of cold detergent,

From the foregoing description, it will be apparent that the operatormay produce a change in operation by actuation of the trigger element M4associated with the spray gun device causing an operational shift inaccordance with an automatic sequence for which the shift registersllfih are programmed. 'lhus, through the control circuit described, thehot rinse solenoid lli'lil and detergent solenoid lldd may be energizedand deenergized in different combinations in order to sequentiallysupply cold water, hot water, hot detergent and cold detergent to theoutlet for discharge from the spray gun and then automatically reset fora new cycle. 80 that the operator will liIIOW what type of cleaningfluid is being discharged at any instant from the spray gun, one of theindicator lamps will be illuminated corresponding to the operationalstage of the apparatus. Further, while injection of the detergent intothe water is disclosed upstream of the heat transfer tube, the presentinvention contemplates injection of detergent downstream of the heattransfer tube as well.

The foregoing is considered as illustrative only of the principles ol"the invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

i. A cleaning apparatus, comprising an insulated tank supported invertical position, containing a body oi" water,

a heat transfer conduit mounted within the tank in heatconductiverelation to the water and comprising a coiled tube having externalheat-conducting fins,

outlet means mounted on the tanlr and connected directly to said heattransfer conduit for discharging liquid at a predetermined temperatureand pressure,

continuously operative pump means for supplying liquid to the heattransfer conduit at an inlet temperature substan tially lower than saidpredetermined temperature,

bypass means for selectively conducting the liquid supplied by the pumpmeans at said inlet temperature directly to the outlet means whilepreventing flow through the heat transfer conduit,

a source of cleaning fluid,

selectively controlled valve means connecting the source to the pumpmeans for supplying a mixture of said fluid and the liquid to the heattransfer conduit, and

heating means mounted within the tank and disposed inwardly of tirecoiled tube, said heating means including fuel burner means, a pluralityof fuel supply tubes connected to the burner means,temperature-controlling valve means controlling flow of fuel through atleast one of the supply tubes, and thermostatic sensing means mounted bythe tanlr within the water for operating the temperature-controllingvalve means.

The combination of claim It wherein the heat'uig means further includesheating conduits conducting flue gas from the burner means upwardlythrough the tanli.

A cleaning apparatus, comprising an insulated tank containing a bodyolheat-storing fluid,

a coiled tube having errternm heat-conducting tins mounted within thetanlr in heat-conductive relation to the heatstoring fluid,

outlet means mounted on the tank and connected directly to said coiledtube for discharging liquid at a predetermined tcrnpcrature andpressure,

continuously operative pump means for supplying liquid to said coiledtube at an inlet temperature substantially lower than said predeterminedtemperature,

bypass means for selectively conducting the liquid supplied by the pumpmeans at said inlet temperature directly to the outlet means whilepreventing flow through said coiled tube,

a source or" cleaning fluid,

selectively controlled valve means connecting the source to the pumpmeans for supplying a mixture or" fluid and the liquid to said coiledtube, and

heating means mounted within the tanlr and disposed inwardly oi thecoiled tube, said heating means including fuel burner means, a pluralityoi? fuel supply to corn nected to the burner means,temporaturecontrolling valve means controlling flow of fuel through atleast one of the supply tubes and thermostatic sensing means mounted bythe tank within the heatstoring liquid for operating thetemperature-controlling valve means.

t. The combination of claim 33 wherein the heat' g means furtherincludes a plurality of heating conduits conducting flue gas from theburner means horizontally through the tanlr, and blower means forinducing llow of said gens through the heating conduits.

5. A cleaning apparatus, comprising an insulated tanlr supported in avertical position and con taining a body of water,

a coiled tube having external heat-conducting fins mounted within thetanlr. in heat-conductive relation to the water, outlet means mounted onthe tanlr and connected directly to said coiled tube for dischargingliquid at a predetermined temperature and pressure,

continuously operative pump means for supplying liquid to said coiledtube at an inlet temperature substantially lower than said predeterminedtemperature, and

bypass means for selectively conducting the liquid supplied by the pumpmeans at said inlet temperature directly to the outlet means whilepreventing flow through said coiled tube,

a source of cleaning fluid,

selectively controlled valve means connecting the source to the pumpmeans for supplying a mixture of said fluid and the liquid to saidcoiled tube, and

heating means within the tank and disposed inwardly of the coileo tube,said heating means including a coiled heating conduit through which aheating fluid circulated.

s. A cleaning apparatus, comprising an insulated tank containing a bodyof heat-storing fluid,

a coiled tube having external heat-conducting fins mounted within thetank in heat-conductive relation to the heatstoring fluid,

outlet means mounted on the tank and connected directly to said coiledtube for discharging liquid at a predetermined temperature and pressure,

continuously operative pump means for supplying liquid to said coiledtube at an inlet temperature substantially lower than said predeterminedtemperature,

bypass means for selectively conducting the liquid supplied by the pumpmeans at said inlet temperature directly to the outlet means whilepreventing flow through said coiled tube,

heating means mounted within the tank and disposed inwardly of thecoiled tube, and further including a plurality of heating conduitsconducting t'lue from the heating means horizontally through the tanlt,and blower means for inducing flow oi? said flue gas through the heatingconduits.

'l. A cleaning apparatus, comprising an insulated. containing a body ofheat-storing fluid,

a coiled tube having external heat-conducting tins moun ted within thetanlr in heat-conductive relation to the heatstoring fluid,

outlet means mounted on the tank and connected directly to said coiledtube for discharging liquid at a predetermined temperature and pressure,

continuously operative pump means for supplying liquid to said coiledtube at an inlet temperature substantially lower than said predeterminedtemperature,

a source of cleaning fluid, and

selectively controlled valve means connecting the source to the pumpmeans for supplying a mixture of said fluid and the liquid to saidcoiled tube,

heating means mounted within the tank and disposed inwardly of saidcoiled tube, said heating means including fuel burner means, a pluralityof fuel supply tubes connected to the burner means,temperature-controlling valve means controlling flow of fuel through atleast one of the supply tubes and thermostatic sensing means mounted bythe tank within the heat-storing liquid for operating thetemperature-controlling valve means.

8. The combination of claim 7 wherein the selectively controlled valvemeans includes solenoid devices for respectively blocking flow of thecleaning fluid and conducting flow of the liquid in the outlet means inbypass relation to the heat transfer conduit, programmed means forenergizing said solenoid devices in accordance with differentoperational stages, pulse-generating means connected to the programmeans for sequentially changing the operational stages, and indicatormeans connected to said programmed means for identifying the operationalstages.

9. A cleaning apparatus, comprising an insulated tank containing a bodyof heat-storing fluid, a

heat transfer conduit mounted within the tank in heatconductive relationto the heat-storing fluid, outlet means mounted on the tank andconnected directly to said heat transfer conduit for discharging liquidat a predetermined temperature and pressure, continuously operative pumpmeans for supplying liquid to the heat transfer conduit at an inlettemperature substantially lower than said predetermined temperature, asource of cleaning fluid, and

selectively controlled valve means connecting the source to the pumpmeans for supplying mixture of said fluid and the liquid to the heattransfer tube, the selectively controlled valve means including solenoiddevices for respectively blocking flow of the cleaning fluid andconducting flow of the liquid in the outlet means in bypass relation tothe heat transfer conduit,

programmed means for energizing said solenoid devices in accordance withdifferent operational stages,

pulse-generating means connected to the programmed means forsequentially changing the operational stages, and

indicator means connected to said programmed means for identifying theoperational stages.

10. A cleaning apparatus, comprising an insulated tank containing a bodyof a first liquid,

a heat transfer conduit mounted within the tank in heatconductiverelation to said first liquid and having an inlet and outlet means,

pump means for supplying a second liquid to the heat transfer conduit atsaid inlet,

a source of cleaning fluid,

selectively controlled valve means connecting the source to the pumpmeans for supplying a mixture of said fluid and said second liquid tothe heat transfer conduit, and

heating means mounted within the tank for imparting heat to said heattransfer conduit, said heating means including fuel burner means,

a plurality of fuel supply tubes connected to the burner means,

temperaturecontrolling valve means controlling flow of fuel through atleast one of the supply tubes, and

thermostatic sensing means mounted by the tank within the heat-storingliquid for operating the temperaturecontrolling valve means.

1].. The apparatus of claim 10 having bypass means for 5 selectivelyconducting said second liquid directly from said pump means to saidoutlet means.

12. in a cleaning apparatus having a tank containing a body ofheat-storing fluid at a predetermined temperature,

a heat exchange tube in the tank in heat-conductive relation to theheat-storing fluid, with an inlet and an outlet,

pump means for supplying liquid to said tube at an inlet temperaturesubstantially lower than said predetermined temperature,

fuel burner means in said tank,

a plurality of fuel supply tubes connected to the burner means,

temperature-controlling valve means controlling flow of fuel through atleast one of the supply tubes,

thermostatic sensing means mounted by the tank within the heat-storingliquid for operating the temperature'controlling valve means,

a source of cleaning fluid, and

selectively controlled valve means connecting said source to said pumpmeans for supplying a mixture of said fluid and said liquid to saidtube.

13. A cleaning apparatus, comprising a tank containing a body of water,

a coiled tube mounted within the tank in heat-conductive relation to thewater,

outlet means for discharging liquid from said coiled tube at apredetermined temperature and pressure,

pump means for supplying liquid to said coiled tube at an inlettemperature substantially lower than said predetermined temperature,

heating means within the tank and disposed inwardly of the coiled tube,said heating means including a coiled heating conduit through which aheating fluid is circulated, and

bypass means for selectively conducting the liquid supplied by the pumpmeans at said inlet temperature directly to the outlet means whilepreventing flow through said coiled tube.

14. A cleaning apparatus, comprising a tank containing a body of water,

a coiled tube mounted within the tank in heat-conductive relation to thewater,

outlet means for discharging liquid from said coiled tube at apredetermined temperature and pressure,

pump means for supplying liquid to said coiled tube at an inlettemperature substantially lower than said predetermined temperature,

heating means within the tank and disposed inwardly of the coiled tube,said heating means including a coiled heating conduit through which aheating fluid is circulated,

a source of cleaning fluid, and

selectively controlled valve means connecting the source to the pumpmeans for supplying a mixture of said fluid and the liquid to saidcoiled tube.

15. A cleaning apparatus, comprising an insulated tank containing a bodyof heat-storing fluid,

a coiled tube mounted within the tank in heat-conductive relation to theheat-storing fluid,

outlet means mounted on the tank and connected directly to said coiledtube for discharging liquid at a predetermined temperature and pressure,

pump means for supplying liquid to said coiled tube at an inlettemperature substantially lower than said predetermined temperature,

heating means mounted within the tank and disposed inwardly of thecoiled tube, and further including a plurality of heating conduitsconducting flue gas from the heating means horizontally through thetank, and

blower means for inducing flow of said flue gas through the heatingconduits.

16. A cleaning apparatus, comprising a tank containing a body ofheat-storing fluid,

a heat transfer conduit mounted within the tank in heatconcluctiverelation to the heat-string fluid and having outlet means fordischarging liquid at a predetermined temperature and pressure,

pump means for supplying liquid to the heat transfer conduit at an inlettemperature substantially lower than said predetermined temperature,

a source of cleaning fluid, and

selectively controlled valve means connecting the source to the pumpmeans for supplying a mixture of said fluid and the liquid to the heattransfer tube,

1. A cleaning apparatus, comprising an insulated tank supported invertical position, containing a body of water, a heat transfer conduitmounted within the tank in heatconductive relation to the water andcomprising a coiled tube having external heat-conducting fins, outletmeans mounted on the tank and connected directly to said heat transferconduit for discharging liquid at a predetermined temperature andpressure, continuously operative pump means for supplying liquid to theheat transfer conduit at an inlet temperature substantially lower thansaid predetermined temperature, bypass means for selectively conductingthe liquid supplied by the pump means at said inlet temperature directlyto the outlet means while preventing flow through the heat transferconduit, a source of cleaning fluid, selectively controlled valve meansconnecting the source to the pump means for supplying a mixture of saidfluid and the liquid to the heat transfer conduit, and heating meansmounted within the tank and disposed inwardly of the coiled tube, saidheating means including fuel burner means, a plurality of fuel supplytubes connected to the burner means, temperature-controlling valve meanscontrolling flow of fuel through at least one of the supply tubes, andthermostatic sensing means mounted by the tank within the water foroperating the temperature-controlling valve means.
 2. The combination ofclaim 1 wherein the heating means further includes heating conduitsconducting flue gas from the burner means upwardly through the tank. 3.A cleaning apparatus, comprising an insulated tank containing a body ofheat-storing fluid, a coiled tube having external heat-conducting finsmounted within the tank in heat-conductive relation to the heat-storingfluid, outlet means mounted on the tank and connected directly to saidcoiled tube for discharging liquid at a predetermined temperature andpressure, continuously operative pump means for supplying liquid to saidcoiled tube at an inlet temperature substantially lower than saidpredetermined temperature, bypass means for selectively conducting theliquid supplied by the pump means at said inlet temperature directly tothe outlet means while preventing flow through said coiled tube, asource of cleaning fluid, selectively controlled valve means connectingthe source to the pump means for supplying a mixture of said fluid andthe liquid to said coiled tube, and heating means mounted within thetank and disposed inwardly of the coiled tube, said heating meansincluding fuel burner means, a plurality of fuel supply tubes connectedto the burner means, temperature-controlling valve means controllingflow of fuel through at least one of the supply tubes and thermostaticsensing means mounted by the tank within the heat-storing liquid foroperating the temperature-controlling valve means.
 4. The combination ofclaim 3 wherein the heating means further includes a plurality ofheating conduits conducting flue gas from the burner means horizontallythrough the tank, and blower means for inducing flow of said flue gasthrough the heating conduits.
 5. A cleaning apparatus, comprising aninsulated tank supported in a vertical position and containing a body ofwater, a coiled tube having external heat-conducting fins mounted withinthe tank in heat-conductive relation to the water, outlet means mountedon the tank and connected directly to said coiled tube for dischargingliquid at a predetermined temperature and pressure, continuouslyoperative pump means for supplying liquid to said coiled tube at aninlet temperature substantially lower than said predeterminedtemperature, and bypass means for selectively conducting the liquidsupplied by the pump means at said inlet temperature directly to theoutlet means while preventing flow through said coiled tube, a source ofcleaning fluid, selectively controlled valve means connecting the sourceto the pump means for supplying a mixture of said fluid and the liquidtO said coiled tube, and heating means within the tank and disposedinwardly of the coiled tube, said heating means including a coiledheating conduit through which a heating fluid is circulated.
 6. Acleaning apparatus, comprising an insulated tank containing a body ofheat-storing fluid, a coiled tube having external heat-conducting finsmounted within the tank in heat-conductive relation to the heat-storingfluid, outlet means mounted on the tank and connected directly to saidcoiled tube for discharging liquid at a predetermined temperature andpressure, continuously operative pump means for supplying liquid to saidcoiled tube at an inlet temperature substantially lower than saidpredetermined temperature, bypass means for selectively conducting theliquid supplied by the pump means at said inlet temperature directly tothe outlet means while preventing flow through said coiled tube, heatingmeans mounted within the tank and disposed inwardly of the coiled tube,and further including a plurality of heating conduits conducting fluegas from the heating means horizontally through the tank, and blowermeans for inducing flow of said flue gas through the heating conduits.7. A cleaning apparatus, comprising an insulated tank containing a bodyof heat-storing fluid, a coiled tube having external heat-conductingfins mounted within the tank in heat-conductive relation to theheat-storing fluid, outlet means mounted on the tank and connecteddirectly to said coiled tube for discharging liquid at a predeterminedtemperature and pressure, continuously operative pump means forsupplying liquid to said coiled tube at an inlet temperaturesubstantially lower than said predetermined temperature, a source ofcleaning fluid, and selectively controlled valve means connecting thesource to the pump means for supplying a mixture of said fluid and theliquid to said coiled tube, heating means mounted within the tank anddisposed inwardly of said coiled tube, said heating means including fuelburner means, a plurality of fuel supply tubes connected to the burnermeans, temperature-controlling valve means controlling flow of fuelthrough at least one of the supply tubes and thermostatic sensing meansmounted by the tank within the heat-storing liquid for operating thetemperature-controlling valve means.
 8. The combination of claim 7wherein the selectively controlled valve means includes solenoid devicesfor respectively blocking flow of the cleaning fluid and conducting flowof the liquid in the outlet means in bypass relation to the heattransfer conduit, programmed means for energizing said solenoid devicesin accordance with different operational stages, pulse-generating meansconnected to the program means for sequentially changing the operationalstages, and indicator means connected to said programmed means foridentifying the operational stages.
 9. A cleaning apparatus, comprisingan insulated tank containing a body of heat-storing fluid, a heattransfer conduit mounted within the tank in heat-conductive relation tothe heat-storing fluid, outlet means mounted on the tank and connecteddirectly to said heat transfer conduit for discharging liquid at apredetermined temperature and pressure, continuously operative pumpmeans for supplying liquid to the heat transfer conduit at an inlettemperature substantially lower than said predetermined temperature, asource of cleaning fluid, and selectively controlled valve meansconnecting the source to the pump means for supplying mixture of saidfluid and the liquid to the heat transfer tube, the selectivelycontrolled valve means including solenoid devices for respectivelyblocking flow of the cleaning fluid and conducting flow of the liquid inthe outlet means in bypass relation to the heat transfer conduit,programmed means for energizing said solenoid devices in accordance withdifferent operational stages, pulse-generatIng means connected to theprogrammed means for sequentially changing the operational stages, andindicator means connected to said programmed means for identifying theoperational stages.
 10. A cleaning apparatus, comprising an insulatedtank containing a body of a first liquid, a heat transfer conduitmounted within the tank in heat-conductive relation to said first liquidand having an inlet and outlet means, pump means for supplying a secondliquid to the heat transfer conduit at said inlet, a source of cleaningfluid, selectively controlled valve means connecting the source to thepump means for supplying a mixture of said fluid and said second liquidto the heat transfer conduit, and heating means mounted within the tankfor imparting heat to said heat transfer conduit, said heating meansincluding fuel burner means, a plurality of fuel supply tubes connectedto the burner means, temperature-controlling valve means controllingflow of fuel through at least one of the supply tubes, and thermostaticsensing means mounted by the tank within the heat-storing liquid foroperating the temperature-controlling valve means.
 11. The apparatus ofclaim 10 having bypass means for selectively conducting said secondliquid directly from said pump means to said outlet means.
 12. In acleaning apparatus having a tank containing a body of heat-storing fluidat a predetermined temperature, a heat exchange tube in the tank inheat-conductive relation to the heat-storing fluid, with an inlet and anoutlet, pump means for supplying liquid to said tube at an inlettemperature substantially lower than said predetermined temperature,fuel burner means in said tank, a plurality of fuel supply tubesconnected to the burner means, temperature-controlling valve meanscontrolling flow of fuel through at least one of the supply tubes,thermostatic sensing means mounted by the tank within the heat-storingliquid for operating the temperature-controlling valve means, a sourceof cleaning fluid, and selectively controlled valve means connectingsaid source to said pump means for supplying a mixture of said fluid andsaid liquid to said tube.
 13. A cleaning apparatus, comprising a tankcontaining a body of water, a coiled tube mounted within the tank inheat-conductive relation to the water, outlet means for dischargingliquid from said coiled tube at a predetermined temperature andpressure, pump means for supplying liquid to said coiled tube at aninlet temperature substantially lower than said predeterminedtemperature, heating means within the tank and disposed inwardly of thecoiled tube, said heating means including a coiled heating conduitthrough which a heating fluid is circulated, and bypass means forselectively conducting the liquid supplied by the pump means at saidinlet temperature directly to the outlet means while preventing flowthrough said coiled tube.
 14. A cleaning apparatus, comprising a tankcontaining a body of water, a coiled tube mounted within the tank inheat-conductive relation to the water, outlet means for dischargingliquid from said coiled tube at a predetermined temperature andpressure, pump means for supplying liquid to said coiled tube at aninlet temperature substantially lower than said predeterminedtemperature, heating means within the tank and disposed inwardly of thecoiled tube, said heating means including a coiled heating conduitthrough which a heating fluid is circulated, a source of cleaning fluid,and selectively controlled valve means connecting the source to the pumpmeans for supplying a mixture of said fluid and the liquid to saidcoiled tube.
 15. A cleaning apparatus, comprising an insulated tankcontaining a body of heat-storing fluid, a coiled tube mounted withinthe tank in heat-conductive relation to the heat-storing fluid, outletmeans mounted on the taNk and connected directly to said coiled tube fordischarging liquid at a predetermined temperature and pressure, pumpmeans for supplying liquid to said coiled tube at an inlet temperaturesubstantially lower than said predetermined temperature, heating meansmounted within the tank and disposed inwardly of the coiled tube, andfurther including a plurality of heating conduits conducting flue gasfrom the heating means horizontally through the tank, and blower meansfor inducing flow of said flue gas through the heating conduits.
 16. Acleaning apparatus, comprising a tank containing a body of heat-storingfluid, a heat transfer conduit mounted within the tank inheat-conductive relation to the heat-storing fluid and having outletmeans for discharging liquid at a predetermined temperature andpressure, pump means for supplying liquid to the heat transfer conduitat an inlet temperature substantially lower than said predeterminedtemperature, a source of cleaning fluid, and selectively controlledvalve means connecting the source to the pump means for supplying amixture of said fluid and the liquid to the heat transfer tube, saidselectively controlled valve means including solenoid devices forrespectively blocking flow of the cleaning fluid and conducting flow ofthe liquid in the outlet means in bypass relation to the heat transferconduit, programmed means for energizing said solenoid devices inaccordance with different operational stages, pulse-generating meansconnected to the programmed means for sequentially changing theoperational stages, and indicator means connected to said programmedmeans for identifying the operational stages.